The biochemistry, physiology and pharmacology of biogenic amines, catecholsteroids, amino acid precursors, metabolic products, various synthetic derivatives as well as related biosynthetic and metabolic enzymes have been investigated. The primary area of study concerns various aspects of catechol-O-methyltransferase (COMT) including; immunohistochemical localization of COMT as well as catecholamine levels in the dental pulp of rat and man; the immunohistochemical localization of the tyrosine hydroxylase, aromatic amino acid decarboxylase,a nd l- DOPA in the dental pulp of rat and man; the effect of RU486 on the induction of COMT in the pregnant rat uterus; the effect on COMT inhibition during day 0 to day 3 of pregnancy on implantation in the rat; a study of the temporal relation between the appearance of COMT, progesterone, and estrogen receptors ina the luminal epithelium of the pregnant rat; the localization of COMT in estrogen-induced tumors of the hamster kidney is in progress; a survey of the correlation of "low" red blood cell-COMT activity with the incidence of adenocarcinomas and other evidences of neoplastic activity in estrogen sensitive tissue sites in women has ben initiated.